Medicinal product with a textile component

ABSTRACT

The present invention relates to a medicinal product with a textile component such as a wound compress having a surface containing a multiplicity of openings arranged in at least two hole patterns. The diameter of one opening of one hole pattern deviates from the diameter of an opening of another hole pattern by about at least a factor of 5. Better wound healing is achieved by adapting the structural and mechanical characteristics of the medicinal product to the characteristics of the target tissue.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a medical product with a textile component, forexample a wound compress, having the features of a multiplicity ofopenings, with at least two patterns of holes with groups of openings,the diameter of one opening of one hole pattern deviating from thediameter of an opening of another hole pattern in each case by about atleast a factor of 5 from one another.

2. Description of the Related Art

In the medical sector, a number of textile products are known which areintended to externally promote wound healing, for example. Known medicalproducts such as wound compresses consist for example of woven fabric,which has the disadvantage that it has a hard surface which adaptspoorly to the wound. For this reason, many wound compresses are made upof knitted fabrics which are soft per se. They also have some degree ofmoisture absorbency. The softness of knitted fabrics arises from themovement of the threads within the interfacing. These abovementionedwound products have the disadvantage that they harden because ofexudates emerging from the wound and thus lose their functional ability.

Known compresses have semipermeable membranes of polyurethane whichpermit the passage and exchange of gases and fluids and have inparticular nonadhesive materials on the surface facing the wound inorder to prevent them from firmly sticking to the wound. This very typeof compress is not able to specifically promote the angiogenesis whichis achieved with the surface structure according to the invention. U.S.Pat. No. 5,465,735 describes such a multi-layer wound dressing with adense nonwoven which is intended in particular to permit less stickingto the wound.

SUMMARY OF THE INVENTION

Further possible uses of medical products with a textile component are,for example, the treatment of abdominal wall defects in the groin areaor for strengthening soft tissue in other places. A correspondingtechnique is described in U.S. Pat. No. 5,569,273 which describes ahexagonal net structure of polypropylene monofilament yarns. Largeopenings are constructed between adjacent vertical mesh rows, into whichbody tissue can grow into the implant because of the pore structure.However, this product does not promote angiogenesis.

EP 870 820 discloses a nonadhesive wound dressing which, across itsactive area, has depressions containing a pharmaceutical carriersubstance. The depressions are intended only for receiving anddelivering an active substance. The nonadhesion of the wound dressing isemphasized.

Finally, EP 931 012 describes a compress which is used for treatingwounds in a moist environment and which, by means of an appropriatechoice of dressing material, is likewise intended not to adhere to thewound.

Taking this prior art as a basis, it is an object of the invention tomake available a medical product which is of the type set out in theintroduction and which specifically influences and promotes angiogenesisand the healing process associated with the latter.

It is also an aim of the invention to ensure that such a medical productalso remains soft in its textile component even after prolonged contactwith the wound.

A further aim of the invention is to ensure that the rigidness of such amedical product can be preset individually at the time of production.

Finally, it is also a further object of the invention to improveangiogenesis and consequently the tissue regeneration in leg ulcers, forexample.

According to the invention, this object is achieved by the fact that thesurface has a multiplicity of openings, there being at least twopatterns of holes with groups of openings, the diameter of one openingof one hole pattern deviating from the diameter of an opening of anotherhole pattern in each case by about at least a factor of 5 from oneanother.

The advantage for the patient of using medical products according to theinvention lies in the more rapid wound healing, in the reduction of thepain associated with wound treatment, in the shorter time spent in aninpatient department, and in the fact that the cost of treating suchwounds is considerably reduced, which is important to the economy. Theseadvantages are achieved by adapting the structural and mechanicalproperties of the medical product to the properties of the tissue inquestion.

In the case of leg ulcers, the main focus of wound healing lies in theregeneration of a physiologically functional vascular system. Woundhealing is to be seen in the context of scar tissue formation. Anintensive scar tissue formation inconveniences the patient because ofthe poor cosmetic aspect and in particular because of limited mobility.Both of these lead to personal anxiety and in many cases to disability.When the wound has healed, there is unfortunately connective scar tissueleft in which the collagen matrix is reconstructed in compact parallelbundles, whereas the meshwork in undamaged skin has mechanically betterproperties.

Rapid vascularization can lead to uncontrolled formation of the skincapillary system. The capillaries themselves influence the orientationof the collagen fibers.

Mechanical signals in the form of the exertion of a controlled pull onthe cells in the wound bed can represent an important activator of thewound response. Mechanical influences on the wound also play a part incollagen genesis because modified stresses during wound closureinfluence scarring. It is assumed that in order to form a normalcollagen architecture a defined physiological mechanical stimulation isrequired with respect to loading and orientation. In the case of scartissue, by contrast, the anisotropy of the collagen network and thedimensions of the collagen fibers are increased.

In contrast to the feature of nonadhesion to the wound bed, on whichfeature emphasis is placed in the prior art, growth of tissue into themedical article is here desired and advantageous.

The invention makes available a wound treatment system developed on atextile basis which controls tissue formation and positively influencesangiogenesis by acting as a framework. The support for the layeraccording to the invention is dependent on the application. The use ofthe medical products according to the invention is possible in manyareas. One area of use concerns the treatment of large wounds, burns orin surgical applications, for example for hernia meshes. Theseprocedures require treatment systems which make it possible to minimizescar formation. At the same time, it is also possible for the medicalproducts to include mannose-6-phosphate or other collagen-regulatingmeans, or factors which promote tissue regeneration, for example growthfactors of the TGF-b family.

The medical product can be used in many applications where theembroidery-specific properties such as the controlled mechanicalproperties of an embroidery, the local variation in the mechanicaldesign and the specific porosity can be of great advantage. In additionto the stated compresses and hernia meshes, these include abdominal wallreplacements, artificial blood vessels and artificial ligaments. In thecase of the latter, the embroidery technique can be used to pass from afirst specific structure, where the ligament is to grow on and whereload transmission takes place, to a second and different structure inthe ligament area. A further application is the formation ofaugmentation embroideries for reconstruction of the jaw bone in thedental sector.

Depending on the desired mechanical and structural properties of thetextile, different yarn types are used. These can include fibrous,multifilament or monofilament yarns, which can also be untreated,antimicrobially pretreated, gel-coated and can be present in differenttiters.

By using embroidery technology, the knot size and the nature of thelinking can likewise be preset.

The invention is described in more detail below on the basis ofillustrative embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic cross section through a medical articleaccording to one illustrative embodiment of the invention,

FIG. 2 is a diagrammatic plan view of a portion of the embroideredsurface of a medical article according to the invention, and

FIG. 3 is an enlarged sectional view of the area of a pore according toFIG. 2.

FIG. 1 shows a medical article 1 according to the invention in adiagrammatic cross section. This medical article is made up of threelayers, for example. A base layer remote from the wound consists ofcompact woven fabric 10 which has an antibacterial action. This alsocontrols the oxygen and water content at the same time.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A spacer layer 11 with high shear force takeup consisting ofgel-modified yarns permits absorption and desorption and the mechanicalbinding of the compress material. The shear force takeup permits thedistribution of local pressure loads, that is to say it has a cushionfunction and permits stress distribution, which leads to uniform loadingof the wound surface and thus avoids negative local stresses. Lastly,the compress 1 has an embroidered layer 12. The fabric 11 is designed asa spacer in relation to the antibacterial layer 10 and as a materialwhich takes up exudate. On this fabric 11, which is advantageouslyformed as a knit, lies the separately produced embroidered layer 12which is preferably connected at its side edges to the compress 1, forexample by ultrasonic welding. Reference number 13 denotes stimulationpoints which are formed in the layer 12, particularly in the embroiderytechnique. In the form represented, they form flat to semi-roundprotuberances, stimulation points 13, facing toward the wound surfaceand they can also protrude from the side facing away from the woundsurface. The stimulation points 13 can all be the same size or candiffer in size individually or in groups. The word “size” in this caserefers both to the height above and below the surface of the embroideryand also to the surface area in the plan view of the figures. Gradientsin size can be provided, for example with the stimulation points 13 withthe largest surface area and the smallest thickness in the middle of anembroidery, and the stimulation points 13 with the smallest surface areaand the greatest thickness at the edges of the embroidery. Any othercombination of thicknesses and surface areas can be used.

An embroidered structure 12 and thus an angiopolar layer is thusprovided near the wound. An angiopolar layer is a layer which permitsthe specific oriented growth of blood vessels into a structure and thusinfluences the density and orientation of the blood vessels in theregenerated tissue. This embroidered structure 12 introducesmorphological features into wound treatment which induce and stimulate aspecific angiogenesis within the framework and thus form thephysiological basis for tissue renewal.

The textile architecture 11 and 12 creates optimum mechanical support,forms a reservoir for exudates and permits optimum control of moistureand gas transport.

With the embroidery technique, highly architectured three-dimensionaltextile structures are obtained which are needed for structuralfunctions, for example pore pattern, for angiogenesis. The embroiderytechnique permits any desired use of materials in base fabrics.

FIG. 2 shows a diagrammatic plan view of a portion of the embroideredsurface 12 of a medical article 1 according to the invention. Thestructures designated with reference number 14 are openings which areprovided in the embroidered pattern and which are substantiallydiamond-shaped here. In other configurations, these shapes can also berectangular, round, elliptic or have another shape.

To positively stimulate angiogenesis, it is particularly advantageousthat the openings at the center of the compress 1 have the greatestaperture area and form corresponding cavities. In the illustrativeembodiment according to FIG. 2, a gradient is provided with which thediameters 17 of the openings provided decrease from the center to theedges.

The openings 14 are arranged in a regular pattern in the illustrativeembodiment shown. The embroidery technology also permits an irregulararrangement of the openings 14 according to further objectives, inparticular with a variation in size.

The fabric 11 mentioned with reference to FIG. 1 and lying behind theembroidered surface 12 acts as a spacer and distributes the weight uponloading in order to prevent decubitus ulcers. The predetermined holecross sections 17 have a size forming a cavity suitable for a bloodcoagulum. They are therefore a support for the tissue-regeneratingelement.

The embroidered surface, of which FIG. 3 shows a section of the area ofa pore 14 according to FIG. 2, has mesoscopic openings 24 in addition tothe apertures or pores 14.

The macroscopic apertures or pores 14 are produced by a plurality oflinks and have a size of the order of 1 to 2 millimeters edge length.They serve for ingrowth of tissue plugs and as a reservoir for the bloodcoagulum from the freshly bleeding wound.

The mesoscopic openings 24 permit ingrowth of individual blood vesselstems and have a size of approximately 100 to 500 micrometers. They areproduced by interfacing of two yarn elements.

Also shown here in diagrammatic representation are microscopic openings34 with a diameter in the range of 5 to 50 micrometers which permit theingrowth of cells and cell aggregates with capillaries if necessary.These openings 34 are between different filaments.

On a still smaller scale, small cavities in the range of 0.5 to 5micrometers are present between individual filaments, and onlyextracellular matrix, for example collagen material, can be deposited inthese.

The openings 14, 24 and 34 form groups of hole patterns. The openings14, the openings 24 and the openings 34 are greater or smaller inrelation to another group of openings by a factor of approximately atleast 5. Within each group the openings can to a certain extent be thesame size or can be of different sizes. The distribution can be regularor also random in the sense that a device for embroidering a textilematerial controls the random distribution of the openings on the wholesurface of the textile material with the aid of a random numbergenerator.

Reference number 13 denotes an embroidery point which, in theillustrative embodiment shown, lies between two edges of thediamond-shaped openings 14. This embroidery point 13 isthree-dimensional relative to the drawing plane and thus the plane ofthe embroidered layer 12 and has in particular a section protruding by 3to 5 mm. In the illustrative embodiment shown, this is almostsemispherical, but can also have other three-dimensional structures.

For example, this embroidery point can also be three-dimensional on theside pointing toward the knitted spacer, in particular in order to forman abutment.

In contrast to known knits, the regular arrangement of the embroideryshown in the figures is not system-related and instead can be changed asdesired in accordance with the use on the basis of the embroiderytechnique. Thus, sequences of large and small apertures 14 are possible.As is shown in FIG. 2, these can have a gradient. The sequence ofembroidery points 13 and openings 14 is purely functional and notdictated by the manufacturing technology of the textile fabric.

It is also possible that the apertures or pores 14 are spanned by acontinuous thread 18 according to FIG. 3, which for example runs fromknot to knot in the embroidery of knots 13.

The interplay of the different hole sizes of the openings 14, 24, 34favorably influences the ingrowth of blood vessels, so-calledangiogenesis. Main growths have a size of 0.5 to 1 mm here. By means ofthe embroidery points it is possible to create a mechanical stimulationin the wound bed, which affords an advantageous design of theembroidered compress material.

Monofilaments, multifilaments or mixtures of these can be used in theembroidery process. The strength of the embroidery can be determinedthrough the choice of yarn and the specified pattern. An advantage overa knit is that the thread cannot move in the interfacings, that is tosay the mechanical properties of the embroidery are defined by thearrangements of the interfacings and are hardly affected by theincorporation of exudate or extracellular matrix into the thread, whichleads to the interfacings sticking together. In knits, by contrast, themechanical properties are mainly defined by the movability of the threadthrough the open interfacing. Thus, an adhesive exudate leads to anincrease in the rigidness of the textile in some circumstances far morethan an order of size. This is a considerable disadvantage for themedical product since the mechanical properties which are crucial forits medical functionality can no longer be controlled. Stiffening cancause local loading conditions which can lead to local tissue necrosis.

In addition to the use of the embroidered element on a textile base suchas a compress, other possible uses can also be envisaged. This caninclude the use of the embroidered surface material on a metallic orceramic base or other wound-treating elements. The embroidery techniquemakes it possible to produce suitable surface elements for eachindividual case.

Having described presently preferred embodiments of the invention, it isto be understood that it may be otherwise embodied within the scope ofthe appended claims.

1. A medical product with a textile component which forms a surface,said surface made from an embroidery, wherein the surface has amultiplicity of openings, there being at least two patterns of holeswith groups of openings, each said hole pattern having a surface, thediameter of one opening of one hole pattern deviating from the diameterof an opening of another hole pattern in each case by about at least afactor of 5 from one another, and wherein a multiplicity of compact,rigid embroidered stimulation points is provided and centrallypositioned between the openings of the surface of each hole pattern,each said compact, rigid embroidered stimulation point having a surface,said stimulation point surface protruding from the textile component byat most several millimeters as a flat to semi-spherical protruberance,and further wherein the stimulation points serve as an angiopolar layerthat inhibits tissue ingrowth thereon.
 2. The medical product accordingto claim 1, wherein the embroidery comprises a structure selected fromthe group consisting of monofilaments, multifilaments, mixtures ofmonofilaments and multifilaments, and staple fiber yarns.
 3. The medicalproduct according to claim 1, wherein the hole pattern with the largerdiameter of its openings and the hole pattern with the second largestdiameter of its openings are arranged regularly.
 4. The medical productaccording to claim 1, wherein the hole pattern with the largestdiameters has the largest opening surface area in the middle of theproduct and decreases in a gradient toward the edges of the product. 5.The medical product according to claim 4, wherein the surface of thecompact, rigid embroidered stimulation points correspond to the surfaceof the hole pattern with the largest diameters.
 6. The medical productaccording to claim 4, wherein each compact, rigid embroideredstimulation point has a height of between about 3 to 5 millimeters. 7.The medical product according to claim 4, having two sides, wherein thecompact, rigid embroidered stimulation points protrude from theembroidered plane of the textile product on both sides of the textileproduct.
 8. The medical product according to claim 1, wherein theproduct comprises a product selected from the group consisting of acompress, a hernia mesh, an abdominal wall replacement, an artificialligament and an augmentation textile for applications in the dentalsector.
 9. The medical product according to claim 1, wherein the textilecomponent comprises an embroidery material selected from the groupconsisting of natural, synthetic, inorganic and mineral raw materials.10. The medical product according to claim 1, wherein said textilecomponent forms a first layer, said medical product further comprising asecond layer which is a knitted spacer layer and a third layer which isa woven base layer.
 11. The medical product according to claim 10,wherein the second layer is capable of taking up exudates and absorbingshear forces and the third layer has an antibacterial action.
 12. Amethod for providing medical product to promote wound healing,comprising the steps of: a) providing a medical product with a textilecomponent which forms a surface, said surface made from an embroidery,wherein the surface has a multiplicity of openings, there being at leasttwo patterns of holes with groups of openings, each said hole patternhaving a surface, the diameter of one opening of one hole patterndeviating from the diameter of an opening of another hole pattern ineach case by about at least a factor of 5 from one another, and whereina multiplicity of compact, rigid embroidered stimulation points isprovided between the openings of the surface of each hole pattern, eachsaid compact, rigid embroidered stimulation point having a surface, saidstimulation point surface protruding from the textile component by atmost several millimeters as a flat to semi-spherical protruberance, andfurther wherein the stimulation points serve as an angiopolar layer thatinhibits tissue ingrowth thereon; and b) applying said medical productto a wound surface.
 13. The method for providing a medical product topromote wound healing of claim 12, wherein the embroidery comprises astructure selected from the group consisting of monofilaments,multifilaments, mixtures of monofilaments and multifilaments, and staplefiber yarns.